This invention relates in general to welding torches and, more particularly, to welding torches for electric arc welding which can be adapted to function interchangeably for electric open arc welding, or for inert gas shielded arc welding.
In the carrying out of electric arc welding operations, it is often necessary or desirable to switch from open arc welding, which employs a consumable electrode, to electric arc welding of a different type employing inert gas shielding and a nonconsumable electrode. For interchangeably performing these two different types of electric arc welding, my U.S. Pat. No. 3,739,140, issued June 12, 1973, discloses and claims a combination welding torch which includes a torch body member connectable to gas, electrical and cooling water supplies, the body member having a head portion encased in an insulating cover, and including a hollow collar having internal screw threading.
If the welder wishes to perform electroc open arc welding, using a consumable electrode, he screws the upper end of a downwardly extending hollow chuck member into the internal collar of the welding head. He then fits a consumable electrode into the downwardly extending splined portion of a chuck member and fits on and screws in place a hollow cylindrical adapter over the upper end of the chuck member with the upper end of the adapter juxtaposed against the lower end of the welding head collar.
If the welder wishes to perform an inert gas shielded arc weld, the consumable electrode arc welding chuck and adapter must be unscrewed. These are replaced in the welding head collar by a three-piece assembly which includes a hollow electrode retainer having a splined chuck member into which is fitted a nonconsumable electrode, and over which is superposed a hollow collar member including a plurality of peripheral gas vents, a hollow ceramic shield being fitted over the assembly.